Ex Parte Chakravarti et al

Patent Trial and Appeal BoardDec 17, 2018

14090194 (P.T.A.B. Dec. 17, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE FIRST NAMED INVENTOR 14/090,194 11/26/2013 Shrikar Chakravarti 27182 7590 12/19/2018 PRAXAIR, INC. LAW DEPARTMENT 10 RIVERVIEW DRIVE DANBURY, CT 06810-5113 UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www .uspto.gov ATTORNEY DOCKET NO. CONFIRMATION NO. 13452-US 5330 EXAMINER CALL,DOUGLASBRYANT ART UNIT PAPER NUMBER 1732 NOTIFICATION DATE DELIVERY MODE 12/19/2018 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): Praxair_IP@Praxair.com ToniAnn_Fonte@Praxair.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte SHRIKAR CHAKRA VAR TI, RAYMOND FRANCIS DRNEVICH, KENNETH L. BURGERS, and MINISH M. SHAH Appeal2018-001478 Application 14/090, 194 Technology Center 1700 Before DONNA M. PRAISS, CHRISTOPHER C. KENNEDY, and JEFFREY R. SNAY, Administrative Patent Judges. PRAISS, Administrative Patent Judge. DECISION ON APPEAL 1 STATEMENT OF THE CASE This is an appeal under 35 U.S.C. Â§ 134 from the final rejection of claims 1-27. Final Act. 2-18; Appeal Br. 11-18. We have jurisdiction under 35 U.S.C. Â§ 6(b ). We AFFIRM. 1 In explaining our Decision, we make reference to the Specification filed November 26, 2013 ("Spec."), the Final Office Action dated December 8, 2016 ("Final Act."), the Appeal Brief filed May 8, 2017 as corrected June 23, 2017 ("Appeal Br."), the Examiner's Answer dated September 22, 2017 ("Ans."), and the Reply Brief filed November 21, 2017 ("Reply Br."). Appeal2018-001478 Application 14/090, 194 The subject matter of this appeal relates to a method and a system for producing a synthesis gas in an oxygen transport membrane based reforming system. Spec. ,r 13. The invention is said to be an improved process for making synthesis gas using a reactively-driven oxygen transport membrane based reforming system comprising an oxidation process occurring at the permeate side of the oxygen transport membranes, which process is exothermic, and a reforming process facilitated by a reformer catalyst, which reforming process is endothermic, in close proximity to the reactively-driven oxygen transport membranes such that heat released in the oxidation process supplies the heat absorbed by the reforming process. Id. ,r 10. A portion of the heated synthesis gas stream exiting the catalyst containing reforming tubes or reactor is recycled by directing it to the permeate side of the oxygen transport membrane elements. Id. ,r 37. According to the Specification, conditioning the combined feed stream to a particular temperature range and steam to carbon ratio results in an optimal operating regime with less reliability problems for the oxygen transport membrane based reforming system due to carbon formation. Id. ,r 4 7. Claims 1 and 16 are illustrative ( disputed limitations italicized): 1. A method for producing a synthesis gas in an oxygen transport membrane based reforming system, wherein said system comprises two distinct reactors: at least one reforming catalyst containing reforming reactor configured to produce a synthesis gas stream by reacting a combined feed stream in the presence of the catalyst and heat; and a reactively driven, oxidation catalyst containing oxygen transport membrane reactor proximate the at least one catalyst containing reforming reactor, the reactively driven oxygen transport membrane reactor comprising a plurality of oxygen 2 Appeal2018-001478 Application 14/090, 194 transport membrane elements configured to separate oxygen from an oxygen containing feed stream and produce an oxygen permeate at a permeate side of the oxygen transport membrane elements and an oxygen depleted retentate stream at a retentate side of the oxygen transport membrane elements, the method comprising the steps of: separating an oxygen containing stream into an oxygen permeate and an oxygen depleted retentate stream using a plurality of oxygen transport membrane elements disposed in the oxygen transport membrane based reforming system; reacting a hydrogen containing stream fed to a permeate side of the oxygen transport membrane elements with the oxygen permeate to generate a reaction product stream and heat; transferring the heat via convection to the oxygen depleted retentate stream and via radiation to at least one catalyst containing reforming reactor configured to produce a synthesis gas stream; pre-treating a hydrocarbon containing feed stream by adding steam to form a pre-treated reformer feed stream; combining the pre-treated reformer feed stream with the reaction product stream to produce a combined feed stream having a steam to carbon ratio between about 1.6 and 3.0 and a temperature between about 5 00 Â°C and 7 5 0 Â°C; reforming the combined feed steam in the at least one catalyst containing reforming reactor in the presence of the catalyst and the heat generated by the reaction of the hydrogen containing stream and permeated oxygen to produce a synthesis gas stream, the at least one catalyst based reforming reactor disposed proximate the oxygen transport membrane elements. 16. An oxygen transport membrane based reforming system for producing synthesis gas which comprises two reactors, said system comprising: a reactor housing; at least one reforming catalyst containing reforming reactor disposed in the reactor housing and configured to 3 Appeal2018-001478 Application 14/090, 194 produce a synthesis gas stream by reacting a combined feed stream in the presence of the catalyst and heat; an oxidation catalyst containing oxygen transport membrane reactor disposed in the reactor housing proximate the at least one catalyst containing reforming reactor, the reactively driven oxygen transport membrane reactor comprising a plurality of oxygen transport membrane elements configured to separate oxygen from an oxygen containing feed stream and produce an oxygen permeate at a permeate side of the oxygen transport membrane elements and an oxygen depleted retentate stream at a retentate side of the oxygen transport membrane elements; a hydrogen containing stream fed to the permeate side of the plurality of oxygen transport membrane elements, wherein the permeated oxygen reacts with the hydrogen containing stream to reactively drive the separation of oxygen from the oxygen containing feed stream and to generate a reaction product stream and heat that is transferred via convection to the oxygen depleted retentate stream and via radiation to at least one catalyst containing reforming reactor; and wherein the combined feed stream comprises a pre- treated reformer feed and the reaction product stream with a steam to carbon ratio between about 1. 6 and 3. 0 and a temperature between about 5 00 Â°C and 7 5 0 Â°C; and wherein the pre-treated reformer feed is at a pressure less than about 20 bar and comprises a mixture of a hydrocarbon feed stream and steam. Appeal Br. 20-21, 23 (Claims Appendix). The Examiner maintains, and Appellants2 appeal, the following rejections: 2 Praxair Technology, Inc. is identified in the Appeal Brief as the real party in interest. Appeal Br. 3. 4 Appeal2018-001478 Application 14/090, 194 1. Claims 16-19 and 21-27 under 35 U.S.C. Â§ I02(a)(l) as anticipated by Repasky (US 2008/0302013 Al, pub. Dec. 11, 2008); 2. Claim 20 under 35 U.S.C. Â§ 103 as unpatentable over Repasky in view of Armstrong (US 2011/0067405 Al, pub. Mar. 24, 2011); 3. Claims 1--4, 6-8, 11, and 13-15 under 35 U.S.C. Â§ 103 as unpatentable over Kelly (US 8,349,214 Bl, iss. Jan. 8, 2013) in view of Repasky; and 4. Claims 5, 9, and 10 under 35 U.S.C. Â§ 103 as unpatentable over Kelly in view of Repasky and Nataraj (US 6,077,323 iss. June 20. 2000); 5. Claims 23 under 35 U.S.C. Â§ 103 as unpatentable over Kelly in view of Repasky and Armstrong; and 6. Claims 1, 2, 4, 9, 11, 12, 16, 18, 20, 26, and 27 on the ground of nonstatutory double patenting as unpatentable over claims 1, 2, 3, 5-8, 10-14, and 16 of US 9,365,422 in view of Repasky. OPINION After review of the arguments and evidence presented by both Appellants and the Examiner, we affirm the stated rejections. Because Appellants indicate that a terminal disclaimer will be filed to address the double patenting rejection (Appeal Br. 18), we summarily affirm that rejection and address below the prior art rejections. Repasky We begin with a description of Repasky, which is cited in each of the prior art rejections. Repasky discloses a staged membrane oxidation reactor system comprising two or more membrane oxidation stages wherein each stage comprises a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, and inlet and outlet regions for each of the reactant gas and an oxidant gas. Repasky Title, Abstract. Figure 1 of Repasky is shown below. 5 Appeal2018-001478 Application 14/090, 194 _ (27 FIG. 1 ~47 " .7 ?c", ,.--Â· ,-rd I i ... :-t:Â·:Â·----- Gee Figure 1 is a schematic flow diagram of Repasky's system. Repasky's system utilizes multiple reactor stages so that reactant conversion in each stage can be controlled; the stages shown in Figure 1 are numbered 1, 3, 5, and 7. Repasky ,r,r 32, 55. Each stage comprises a generic module having an oxidant side (e.g. 5a), a membrane (e.g. 5b), a reactant side (e.g. 5c), and an optional catalyst (5d). Id. ,r 56. The catalyst is included to enhance the reactions occurring therein and may include a steam reforming catalyst. Id. ,r 39. The optional catalyst is shown immediately following the membrane module, but may be disposed within or around the module in any desired configuration. Id. ,r,r 55-56. Rejection 1: Anticipation of Claims 16-19 and 21-27 It is the Examiner's position that Repasky anticipates claims 16-19 and 21-27 for the reasons stated on pages 2-5 of the Final Action and pages 2-5 of the Answer. Appellants argue the subject matter of claim 16 and rely on those same arguments for claims 17-19 and 21-27, which depend from claim 16. 6 Appeal2018-001478 Application 14/090, 194 Appeal Br. 11-14. In accordance with 37 C.F.R. Â§ 4I.37(c)(l)(iv), claims 17-19 and 21-27 will stand or fall together with claim 16. In the Appeal Brief, Appellants argue that the Examiner erred in finding that Repasky teaches two distinct reactor types within a reactor housing as required by the claim. Appeal Br. 11-12. According to Appellants, Repasky discloses a membrane reactor and all reforming in Repasky is conducted in the presence of oxygen supplied by the membrane and in a membrane reactor while all reforming in the system of claim 16 is conducted in a non-membrane reactor in the presence of steam. Id. at 12- 13. The Examiner responds that Repasky discloses a membrane oxidation reactor system consisting of a plurality of membrane modules, modules containing one or more catalysts to enhance the reactions, and various combinations including steam reforming in separate modules immediately following the permeable membrane modules. Ans. 1 7-18 ( citing Repasky ,r,r 22, 31, 39, 40, 43, 56, Fig. 1). The Examiner finds that Repasky discloses the catalysts following the permeable membrane modules are separate and distinct reactor types in separate vessels and that these overall modules may be co-located within a single pressure vessel or reactor housing. Id. at 18 ( citing Repasky ,r,r 39, 56, 57). In the Reply Brief, Appellants contend that Repasky "does not disclose separate and distinct reactor types in separate vessels as alleged by the examiner," but, rather, Repasky discloses a single reactor type enclosed within a single pressurized vessel. Reply Br. 2-3 ( citing Repasky ,r 57). Appellants note that Repasky defines a stage as an assembly of one or more membrane modules and argue that because Repasky describes one or more 7 Appeal2018-001478 Application 14/090, 194 ion transport membranes separating the oxidant zone from the reactant zone, the reactions occurring within the stage mean the reactions are all occurring within the membrane stage, not in a separate and distinct non-membrane based reforming reactor. Id. at 4 (citing Repasky ,r,r 37, 57). We review the appealed rejection for error based upon the issues identified by Appellants and in light of the arguments and evidence produced thereon. Cf Ex parte Frye, 94 USPQ2d 1072, 107 5 (BP AI 2010) (precedential) (cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011) ("it has long been the Board's practice to require an applicant to identify the alleged error in the examiner's rejections")). We find Appellants' arguments directed to claim 1 unpersuasive of reversible error for the following reasons. Appellants do not dispute the Examiner's finding that Repasky teaches an optional catalyst that is shown in Figure 1 as immediately following the oxygen permeable membrane module. Ans. 18; Repasky ,r 56. Nor do Appellants dispute that the optional catalyst disclosed by Repasky is a steam reforming catalyst. Final Act. 3; Repasky ,r 39. Instead, Appellants argue that Repasky does not explicitly teach that the oxygen permeable membrane module and the steam reforming catalyst are in separate reactors. Reply Br. 2--4; Appeal Br. 11-13. However, the Examiner's finding (Ans. 18) that Figure 1 depicts separate modules for the permeated oxygen and the steam reforming whereby the modules containing steam reforming catalysts are immediately following the modules containing permeable membranes is supported by the preponderance of the evidence cited in this appeal (Repasky ,r,r 39, 56, Fig. 1 (items Id, 3d, 5d, 7d following items 1 b, 3b, 5, 7b)). Repasky refers to the catalyst modules (labeled "d" in Figure 1) as 8 Appeal2018-001478 Application 14/090, 194 being in the same "stage" (labeled 1, 3, 5, or 7) as the modules containing permeable membranes (labeled "c" in Figure 1 ), but Repasky's definition of "stage" includes one or more modules rather than a single reactor as Appellant contends (Repasky ,r 37). In addition, Repasky discloses multiple configurations for disposing the optional catalyst, including within or between the membrane modules within any stage (Repasky ,r 39). Appellants' argument that Repasky does not disclose separate reactors in a housing is also unpersuasive because Appellants do not dispute the Examiner's finding that Repasky teaches multiple modules within a single pressure vessel or reactor housing (Ans. 18). The Examiner's finding is supported by the record cited in this appeal. Repasky ,r 57. Appellants do not rebut the Examiner's finding ( Ans. 18) that Repasky discloses its catalyst as immediately following the membrane module, rather than only being disposed within the membrane module. The Examiner's finding on this point is supported by the record and negates any argument that Repasky's optional catalyst is necessarily in the same reactor as Repasky's oxygen permeable membrane. Repasky ,r,r 39, 56, Fig. 1. Therefore, we are not persuaded by Appellants' argument that Repasky does not teach a reforming catalyst containing reforming reactor and an oxidation catalyst containing oxygen transport membrane reactor both disposed in a reactor housing as required by claim 16. For the foregoing reasons, we affirm the Examiner's rejection of claims 16-19 and 21-27 under 35 U.S.C. Â§ 102(a)(l) as anticipated by Repasky. 9 Appeal2018-001478 Application 14/090, 194 Rejection 2: Obviousness of Claim 20 Claim 20 depends from claim 16 and further requires that the system comprise "an ejector, educator, or venturi based device coupled to the permeate side of the oxygen transport member elements .... " The Examiner finds that Armstrong discloses utilizing a venturi to mix the non- permeate gas ( feed gas) and permeate from the membrane and that a person having ordinary skill in the art would have been motivated to utilize the venturi of Armstrong in the apparatus of Repasky to provide a thoroughly mixed stream. Final Act. 7. In the Appeal Brief, Appellants argue that Armstrong fails to cure the deficiencies of Repasky, namely, the alleged failure of Repasky to disclose or suggest a system that requires two distinct sets of reactors. Appeal Br. 14. Because we are not persuaded by Appellants that the Examiner erred in finding that Repasky discloses two separate reactors for the reasons discussed above in connection with claim 16, we likewise are not persuaded that the Examiner reversibly erred in rejecting claim 20. Accordingly, we affirm the Examiner's rejection of claim 20 under 35 U.S.C. Â§ 103. Rejection 3: Obviousness of Claims 1-4, 6-8, 11, and 13-15 It is the Examiner's position that Kelly in view of Repasky suggests the subject matter of claims 1--4, 6-8, 11, and 13-15 for the reasons stated on pages 8-13 of the Final Action. Appellants argue the subject matter common to claim 1. Appeal Br. 15-17. In accordance with 37 C.F.R. Â§ 4I.37(c)(l)(iv), claims 2--4, 6-8, 11, and 13-15 will stand or fall together with claim 1. 10 Appeal2018-001478 Application 14/090, 194 In the Appeal Brief, Appellants argue that the combination of Kelly and Repasky does not disclose the method of claim 1 because the combination does not teach or suggest combining the reaction product stream exiting the membrane reactor with the pre-treated reformer feed stream to produce a combined feed stream having the specified steam to carbon ratio and temperature characteristics needed to minimize carbon formation in the system. Appeal Br. 15-1 7. The Examiner responds that claim 1 does not require reducing carbon formation to any measurable level, however, Kelly teaches that the steam to carbon ratio must be carefully managed and controlled to prevent coking, suggesting that determining the appropriate steam-to-carbon ratio would have been controllable through routine experimentation. Ans. 19 ( citing Kelly 11 :26-30). The Examiner further finds that Kelly discloses a typical reformer operating temperature range that overlaps the claimed range. Id. The Examiner also notes that Repasky was cited for disclosing a steam to carbon ratio of about 1.5 to minimize carbon deposition as desired by Kelly (id. at 20) and that Repasky is relied upon for teaching the claimed temperature range for the purpose of decreasing soot formation (id. at 19). Regarding the combined feed stream required by claim 1, the Examiner finds that Kelly explicitly discloses a hydrogen-containing stream is reacted with oxygen passing through the at least one oxygen transport membrane to form a heated reaction product stream which is then combined with a reactant stream to form a combined reformer feed stream comprising hydrocarbons supplied by the reactant stream with steam contributed to at least by the heated reaction product stream. Id. at 19-20 (citing Kelly 3:34-- 59). 11 Appeal2018-001478 Application 14/090, 194 In the Reply Brief, Appellants contend that "Repasky is directed to an entirely different reforming system where all of the reforming is conducted in a staged membrane reactor [whereas] Kelly's system comprises two types of separate and distinct reactors: a non-membrane reforming reactor and a membrane reactor." Reply Br. 8. Thus, Appellants contend that the combination of Kelly and Repasky is based on hindsight because they reform according to different processes. We are not persuaded of reversible error in the rejection of claim 1 over the combination of Kelly and Repasky under 35 U.S.C. Â§ 103 because we find Repasky discloses separate reactors for the reasons discussed above in connection with claim 16. In addition, Appellants do not dispute the Examiner's finding (Ans. 19--20) that Kelly discloses a combined feed stream. Appellants also do not adequately rebut the Examiner's findings (Ans. 19; Final Act. 8-9) that (1) Kelly teaches carefully managing and controlling the steam to carbon ratio to prevent coking, suggesting that the appropriate steam-to-carbon ratio would have been determined by a skilled artisan through routine experimentation, and (2) Kelly discloses a typical reformer operating temperature range that overlaps the claimed range. The Examiner's findings are supported by the preponderance of the evidence in the cited record on appeal. Kelly 3:34--59, 8:64--67, 11 :26-30. Accordingly, we affirm the Examiner's rejection of claims 1--4, 6-8, 11, and 13-15 under 35 U.S.C. Â§ 103. Rejections 4 and 5 Appellants contend that the Examiner erred in rejecting claims 5, 9, 10, and 12 over the combination of Kelly and Repasky in view of secondary 12 Appeal2018-001478 Application 14/090, 194 references because the secondary references do not cure the alleged deficiencies discussed above in connection with the rejection of claim 1 over Kelly and Repasky. Appeal Br. 17-18. Because we are not persuaded by Appellants that the Examiner reversibly erred in rejecting claim 1 over the combination of Kelly and Repasky for the reasons discussed above in connection with claim 1, we likewise are not persuaded that the Examiner reversibly erred in rejecting claims 5, 9, 10, and 12. Accordingly, we affirm the Examiner's rejections of claims 5, 9, 10, and 12 under 35 U.S.C. Â§ 103. CONCLUSION We affirm all of the Examiner's rejections of claims 1-27. No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. Â§ 1.136(a)(l )(v). AFFIRMED 13